農業機械学会誌
Online ISSN : 1884-6025
Print ISSN : 0285-2543
ISSN-L : 0285-2543
28 巻 , 2 号
選択された号の論文の14件中1~14を表示しています
  • 川村 登, 中谷 正一, 岡本 嗣男, 唐橋 需
    1966 年 28 巻 2 号 p. 67-72
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    An automatic torque control system for the rotary tiller mounted on the four-wheel tractor was studied theoretically and in field experiments. Its automatic control system is shown in Fig. 1. Engine torque is transmitted through the gear train A, B, C, and the gear B is allowed to move perpendicular to the center line of the gear train. This displacement is constrained by the spring S and transfered to the control valve, which actuates the rotary tiller to lift or to fall down by the hydraulic power cylinder, in accordance with the increase or decrease of the resistance torque of power tiller caused by the pitching of the tractor or the change of soil conditions.
    Its block diagram is shown in Fig. 4, and its frequency response of this system in Fig. 7. The field experiments were done crossing the compacted soil strip, the ridge and the ditch shown in Fig. 5. The automatic controlled power tiller proved fairly good response to the outer disturbance.
  • 梅田 重夫, 小野 允久
    1966 年 28 巻 2 号 p. 73-77
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    Measurements of forces acting on three-points fixed link hitch in rotary tillage were made. The characteristics of the forces in tilling were summarized as follows.
    1. Upper link forces were tension and increased with the tilling depth, but they became compression over some depth or by use of the depth gage.
    2. Lower link forces acted toward the tractor, but acted in the opposite direction when the tilling depth were large.
    3. Lift rod forces were compression.
    4. Forces acting on links were affected by the shape and size of link hitch, and the relative arrangement between rotary tilling attachment and tractor.
  • 金須 正幸, 国府田 佳弘, 八木 茂
    1966 年 28 巻 2 号 p. 78-81
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    Two methods to calculate slip coefficient which are more accurate and simpler than Janossi's and Reece's were found.
    (1) The 0.63 times method: The j value when τ is 0.63 times τmax on τ—j curve corresponds to K value by Janossi's tangential method.
    (2) The maximum method: If j0, the j value when the shearing strength becomes maximum value, is kown, K is given by the following equation.
    K=j0/4.6
    (3) The 0.63 times method is suitable to predict the tractor performance in usual field work, and maximum method is suitable to know the maximum tractive force of tractor on the soil.
  • 居垣 千尋, 松井 範義
    1966 年 28 巻 2 号 p. 82-84,81
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    In using the two-way plow, it is found advantageous to work by the succesible or cycloidal plowing method in the central part of the field, and by the additional plowing method in the head-land. In this case, as mentioned in report 6, the turning time of the tractor will be somewhat longer than an expected value from a calculation by slowing down the turning speed and by some other reasons.
    An experiment was carried out in a square land setting the two-way plow of 16 in, width onto the tractor, which is shown in table 1, and efficiency curves of plowing methods resulted from the experiment are shown in figure 2. It will be seen from the figure that efficiency of the cycloildal plowing is generally about 2.5% higher than that of the succesible plowing method. Moreover, efficiency curves of both cycloidal and succesible plowing methods are less than 50% in small area, while they raise quadratically when area becomes larger, approaching 90% in the largest area. Interrelationship between plowing widths and the efficiency of both cycloidal and succesible plowiing methods appears constant. Table 2 is the results of calculations for the relationships.
    Capacities of the two-way plow are shown in figure 3. They were obtained multiplying plowing widths by plowing speeds and using efficiency values mentioned above.
    In the figure, we can see a tendency that the wider the plowing width the higher the capacity, and a remarkable increase of the capacity when area becomes larger. Therefore, in an actual case, it would be better to broaden the width of the plow as much as, possible considering ability of the tractor and the field condition. In the two-way plow, however, as the weight would be doubled comparing with a one-way plow, there is certain limitation in setting such a broadened plow. Consequently, if there is no special require, reversible plow of the normal type, except for the front-rear symmetry reversible type noted in report 8, would not be efficient.
  • 田辺 一, 来田 茂, 増田 治策, 川崎 健
    1966 年 28 巻 2 号 p. 85-89
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    To find the steering characteristics of 4 wheel tractor on the slope field, some tests were carried out on the idle running locus of each wheel under the condition of constant steering angle of front wheel.
    The test results are summarized as follows:
    A tractor aiming to travel along the contour line with constant steering angle δ must have an upward deflecting angle of the center line of tractor body α against the contour line.
    The direction of the deflecting angle of tractor is different from the running direction of the tractor, and the different angle of them γ increse with the increasing of angle of the land inclination. Hence, difference γ represents (δ+β+toe in). The curvature K and the locus are decided by γ.
    The skid angle β increases with the increasing of the angle of land inclination, that is, the skid is proportional to the downward tangential component of the tractor weight. The increasing rate of the skid angle of the front wheel is larger than that of the rear wheel. Substituting γ into eq. (9), (10), (15) and (16), the shapes of locus and the curvature are decided. And there is a steering angle at which the curvature becomes 0, that is, A is 0 on the eq. (17) “y=Ax2+Bx”, and then tractor will travel downward from the contour line, because of B<0. At the other steering angles, the travelling locus of tractor will show parabolic curve given by eq. (17). Hence, in order to operate the tractor along the contour line on the slope field, the steering angle of front wheel should be adjusted at all times.
  • 岡村 俊民, 高畑 英彦, 伊藤 道秋, 外館 隆二
    1966 年 28 巻 2 号 p. 90-94,99
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    The handy bean planter developed in Hokkaido have the inclined plate cell type seed metering device.
    According to the laboratory test with sugar beet seeds, the proper peripheral speed of cell is 0.20-0.27m/sec for ball, 0.20m/sec for segmented seed. The proper cell diameter is 30% larger than the average diameter of seeds. When the inclination of seedplate was more than 50 degree, the seeder can not make precise planting.
    The thickness of the seedplate should be same as the diameter of seeds. When the plate thickness is larger than the seed diameter, the seeds are blocked in the cell, especially in the case of segmented seed.
  • 田辺 一, 中尾 清治
    1966 年 28 巻 2 号 p. 95-99
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    To know about the velocity distribution of wind from a fan, this study was done firstly about the relation between the various forms of wing and the wind velocities at near points from the wings, and about the expression of the distribution of wind velocity jetting from the nozzle which is assumed as a point. In this case, the distributions of the wind velocity are expressed in the following form,
    U=KUoz-1exp{-2√2/3ck(r/z)3/2}
    where r is the radial distance from the center axis of jet flow,
    z is the distance from the original point along the center axis,
    c and k are the coefficients of the diffusion of a jet flow and the mixing length respectively,
    K is constant.
    Then applicating it to the jet flow from the limited wing radius on which initial wind velocity was led, the wind velocities in any place are decided as a sum of the following three velocities.
    U1=∫PQKz-1f(n)exp{-2√2/3ch(n-r/z)3/2}dn
    U2=∫QRKz-1f(n)exp{-2√2/3ck(r-n/z)3/2}dn
    U3=∫SHKz-1f(n)exp{-2√2/3ck(r+n/z)3/2}dn
    U=U1+U2+U3
    where n is the auxiliary variable of r and f(n) is a function of the initial wind velocity.
    The integrating ranges are decided according with the length of wing and the radius of center boss.
    This expression was correspondent to the experimental data through a home fan counting c=0.22 and K=0.16, but these coefficients must be consulted by many practical uses of Helicopter and Speed Sprayer etc.
  • 垂井 不二男, 杉原 収
    1966 年 28 巻 2 号 p. 100-102,106
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    The authors discoverd the appearance of unclosed and cracked glume in unhusked paddy harvested by Combine-harvester in 1964.
    In this investigation, we traced the relation between outbreak of the abnormal unhusked paddy and adjustment of combine-harvester and also experimented drying method for abnormal paddy.
    Concerning the outbreak of abnormal unhusked paddy treated by combine-harvester, we discoverd that the outbreak occured in close relation with the cylinder speed:—the higher the speed, the more abnormal paddy appeared. Abnormal unhusked paddy also increased when cylinder clearance was excessively wide or narrow, flow of stuff fed into the cylinder was less, weight ratio of grain to straw was less, and grain moisturec ontent was about 24%.
    Abnormal unhusked paddy produced from combine-harvester dried up at higher speed than normal one, and was easy to crack when it was ventilated under the same condition. It was considered that drying characteristics of abnormal paddy falls some where between normal unhusked paddy and husked one.
  • 竹内 龍三
    1966 年 28 巻 2 号 p. 103-106
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    On the occasion of two viscous turbulent flow in the theory of turbulence boundary layer cause the incompressive symmetric mixing flow at the contact point, the thickness of mixing range of turbulence was decided. The winnower breadth was calculated by induction method, and the author checked up whether this breadth was suitable or not.
    The calculation of winnower breadth was made to apply the mean velocity of turbulent flow that was in measuring points of air velocity by previous report. The maximum permissible length was decided by drawing curve parallel to curve that measured the real height at points of grain separation.
    The calculation was applied at the inlet point, the grain flowing plate, and the way out of main winnower and sub-winnower of the experimental rice huller.
    As the result, this condition was fully satisfied, because the practical breadth at each way out was smaller than the calculated size.
  • 酒井 学
    1966 年 28 巻 2 号 p. 107-109
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    Some Atterberg consistency constants (Att. consts.) of feces of livestock were investigated, considering their relations to mechanical handling. Results obtained may be summarized as follows:
    1. Att. consts. of feces of dairy cattle, sheep and goat are larger than those of swine, which are, however, considerably larger than those of Nasu volcanic sandy loam.
    2. Among the same kind of livestock, the increase of feeding rate of roughage makes Att, coasts. larger, perhaps because of intertwining effect of crude fiber.
    3. The relations between Att. consts. and moisture contents of feces in the barn suggest that adding a small quantity of water to the surface will be able to prevent adhesion of feces to manure implements.
    4. It seems to be preferable to float away clotted feces than to liquefy them with large amount of water.
  • 岡田 芳一
    1966 年 28 巻 2 号 p. 110-113
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
    In order to measure the slippage of wheel tractors at fields, a recording slip meter which could simply measure it has been developed.
    The principal parts of this meter (Fig. 1) are composed of friction disks which regulate the ratio of front wheel radius to rear one, of differential gear by which the slipped revolutions were taken out and of recording apparatus.
    When examined with a wheel tractor on an asphalt pavement, the characteristics of this meter were almost regarded to be satisfied.
  • 石橋 貞人
    1966 年 28 巻 2 号 p. 114-116
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
  • 平田 孝三
    1966 年 28 巻 2 号 p. 117-120
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
  • 1966 年 28 巻 2 号 p. 121-122
    発行日: 1966/09/01
    公開日: 2010/04/30
    ジャーナル フリー
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